Recent posts on this site have pointed out that there are some problems with Windows7 dying and leaving a black screen…and nothing else after logon. The problem causes the desk-top, task bar, system tray and sidebar to completely disappear. That is the Black Screen of Death, (not to be confused with the other BSOD…blue screen of death). Preliminary investigations point to some security patches that were installed on Window7 computers. But Microsoft has issues with that conclusion.
Microsoft has responded, for better or for worse. The problem they say may have been caused by a virus, not a security patch, and not by the patches that became available in November 10, 2009.
The problem comes from patches for Windows7, Vista, and XP, make changes to the Access Control list which then affect applications and stop the OS from running. The ACL is a set of permissions for a logged-on user and the permissions interact with registry keys, creating visible desktop features such as a gadget.
There is fix as reported on this site. Initially it came from the British security firm Prevx. A spokesman for Prevx, Dave Kennerley, mentioned that Windows has at least 10 different issues that could potentially cause a black screen.
But Microsoft’s response has been: “The company has found those reports to be inaccurate and our comprehensive investigation has shown that none of the recently released updates are related to the behavior described in the reports. While we were not contacted by the organization who originally made these reports, we have proactively contacted them with our findings.”
Microsoft denies that its
- patches caused the problem or that
- changes made to the malicious software removal tool caused the problem, or
- non-security related patches caused the problem, or
- that the security patches made changes to the permissions registry (the ACL).
